Negative tone epoxide molecular resists and materials for next generation lithography

Lithography;Photoresists;Molecular resists;Negative tone;E-beam lithography;EUV lithography

Narcross, Hannah ; Henderson, Clifford L. Ludovice, Peter J. Tolbert, Laren M. Chemistry and Biochemistry Bucknall, David G. Collard, David M. Silva, Carlos ; Henderson, Clifford L.

University:Georgia Institute of Technology

Department:Chemistry and Biochemistry

关键词: Lithography;    Photoresists;    Molecular resists;    Negative tone;    E-beam lithography;    EUV lithography;   

Others  :  https://smartech.gatech.edu/bitstream/1853/61699/1/NARCROSS-DISSERTATION-2019.pdf

美国|英语

来源: SMARTech Repository

【 摘 要 】

The ability to quickly and accurately form nanoscale two-dimensional structures is critical for the high-volume manufacturing of semiconductors and microelectronic devices. Significant progress has been made in developing new exposure sources for next-generation lithography, but scaling challenges, especially at sub-20-nm features will require new materials capable of meeting the strict performance requirements laid out by the International Technology Roadmap for Semiconductors. Organic molecular resists have been proposed as a possible alternative to traditional polymeric photoresists due in part to their smaller molecular weight and narrower dispersity, but have yet to meet the necessary resolution, line edge roughness, and sensitivity standards for next-generation lithography. One promising type of organic resists are negative-tone photoresists based on the cationic polymerization of epoxides, due to their resistance to pattern collapse which is a common source of patterning failure at sub-100-nm length scales. This thesis will discuss some of the research that has been conducted on understanding structure-property relationships governing the patterning performance of these materials and developing novel additives to improve their performance including cross-linkable photoacid generators capable of use at ultra-high loadings to improve sensitivity and line edge roughness, and phenol-functionalized polymerization control additives to improve resolution. An alternative lithographic technique that has attracted growing interest over the years is the directed self-assembly (DSA) of block copolymers which offers a means to extend the use of older lithographic technologies or be used complementarily with newer exposure sources. DSA requires that a substrate be patterned chemically (chemoepitaxy) and/or topographically (graphoepitaxy) with guiding patterns in order to form lithographically useful orientations of morphologies with long range order and low defectivity. This thesis will also discuss some progress made towards developing a non-chemically amplified photodefinable underlayer which can have arbitrary guiding patterns directly written onto it using current (298 and 193 nm) or next-generation (extreme ultraviolet and electron-beam) exposure sources.